BISPHENOL-A

Fetuses exposed

A new UCSF study detected bisphenol-A in all umbilical cord blood collected from 85 pregnant women, suggesting that fetuses are universally exposed to the controversial compound found in hard plastics and metal food cans.

Bisphenol-A at varying levels was identified in all the samples. And levels in more than one-third of the samples were similar to or above those previously associated with developmental effects in animals, researchers said.

Many scientists believe bisphenol-A is an endocrine-disrupting chemical that can be toxic in low doses.

BREAST CANCER

Aggressive cells

Breast cancer cells can become more aggressive the more they are exposed to small doses of cadmium, a heavy metal found in air, water, food and makeup, according to a new study from Dominican University of California in San Rafael.

The finding came about when researchers exposed breast cancer cells in a lab to low concentrations of cadmium for more than six months.

The breast cancer cells showed an increased ability to invade and move through organs and tissues - characteristics of more advanced-stage cancers. The cells also expressed higher levels of a protein associated with tumor invasion and metastasis.

Cadmium can act as an endocrine disruptor that changes levels of estrogen, a hormone. These changes in turn can lead to abnormal growth of cells in the mammary gland, resulting in breast cancer.

The study was published last week in Plos One.

- Stephanie M. Lee

Sugar

Powering up

A new study from Stanford suggests that an afternoon trip to the office vending machine for a sugary pick-me-up may not be the best way to power through the rest of the day.

Psychologists conducted a series of experiments on willpower, defined in the study as the ability to resist temptation and stay focused on a difficult task.

Theories on willpower commonly suggest that it is a mechanism easily depleted, and past research has suggested self-control is enhanced by glucose.

In the study, though, people who held a belief that willpower is an abundant resource didn't require sugar to complete two difficult tasks - the willpower was in their minds, rather than a candy bar. Sugar consumption made no difference in their self-control, researchers found.

Those who believed willpower is limited in supply, however, exhibited improved self-control after consuming sugar. Those people, the study suggested, might constantly be looking for cues that their own willpower is lagging - and looking for something such as sugar to give it a boost.

DIABETES

Hormone's role

A new Kaiser Permanente study found that levels of a specific hormone may predict a woman's risk for developing gestational diabetes, a common condition where non-diabetic women experience high blood glucose levels during pregnancy. The condition poses some risks to a baby's health.

In the study, overweight women with low levels of the hormone adiponectin - which protects against insulin resistance - were nearly seven times more likely to develop gestational diabetes than those with normal levels of the hormone. Normal-weight women with low levels of the hormone were also 3.5 times more likely to develop the condition.

Overweight women with high levels of the hormone were only 1.7 times as likely to develop gestational diabetes.

Researchers retrospectively examined electronic health records of more than 4,000 women who gave voluntary blood samples during routine appointments between 1985 and 1996 and later had a baby.

- Kristen V. Brown

PROSTATE CANCER

Imaging tumor growth

Sugar could provide a new, non-invasive way for doctors to get precise images of prostate tumors and possibly be able to tell which cancer medications would be most effective, UCSF researchers have found.

In a study, which began in December 2010, UCSF and GE Healthcare researchers injected 31 prostate cancer patients with a natural sugar compound called pyruvate, which tends to be converted into a different compound called lactate when cancer is present.

Using MRI technology, the team then followed pyruvate and its conversion into lactate in the prostate. Higher, more intense signals in the imaging indicated a quicker conversion to lactate, which suggest a more aggressive tumor. Very limited conversion is detected in a normal prostate.

While commercial use of the technology is estimated to be five to 10 years away, scientists believe it could offer oncologists real-time feedback about whether a patient's seemingly slow-growing cancer has started to progress or how an ongoing treatment is working. Many patients have slow-growing disease, but that still can be difficult to predict.

The UCSF team has received grants to continue the research in prostate cancer as well as to extend studies to cancers of the brain, breast, liver, lymph glands and pancreas. The findings appeared last month in the journal Science Translational Medicine.

THYROID HEALTH

Biopsy clues

Many patients undergo biopsies for thyroid nodules while less than 2 percent turn out to be cancerous.

A team of UCSF researchers has called for clearer guidelines that doctors can follow to help reduce the number of unnecessary procedures.

They analyzed the medical records of about 8,800 UCSF patients who underwent thyroid ultrasound scans from January 2000 to March 2005 and found that simply the presence of a thyroid nodule didn't indicate cancer in the vast majority of cases.

The team recommended biopsies should be performed only when medical imaging reveals a thyroid nodule with tiny flecks of calcium called microcalifications, or one that is more than 2 centimeters in diameter and is completely solid rather than cyst-like.

The researchers published the study and the recommended guidelines online Aug. 26 in JAMA Internal Medicine.

- Victoria Colliver

ALZHEIMER'S DISEASE

Tau research

Scientists at the Gladstone Institutes have engineered neurons that carry a specific gene mutation that may be a cause of Alzheimer's disease and other forms of dementia.

The work is important first because it demonstrates that engineering brain cells to study in a lab is possible, and second because it shows a possible target for drug therapy to prevent the buildup of a certain protein that may cause those diseases.

The scientists took skin cells from a patient known to have a genetic mutation that leads to a buildup of the protein tau in the brain. That protein buildup has long been associated with development of Alzheimer's.

Using the patient's skin cells, scientists regressed them into a stem cell state, and then engineered those stem cells into neurons. They made some neurons with the genetic mutation, and in other neurons they corrected the mutation.

In the neurons with the mutation, the tau proteins built up to toxic levels. In the other neurons, the tau was flushed out.

A paper on the engineering process and the tau research was published Aug. 29 in the journal Stem Cell Reports.